Field
Exemplary embodiments relate to a cloud-based mail system and a mail service method for providing improved security.
Discussion of the Background
In general, an electronic mail (e-mail) system includes servers configured to transmit and receive emails, and a storage configured to store the emails. In the related art, companies have built servers and storage as a separate infrastructure for an email system.
Currently, many companies are utilizing a cloud mail service instead of constructing a separate self-infrastructure. Using the cloud mail service, an infrastructure, for example, equipment, a space for equipment, and a network, used to construct the e-mail system is not required for service providers, such as companies used to construct an email system. Costs for operating the e-mail system, such as processing spam e-mail, may be reduced by using cloud-based email systems.
FIG. 1 is a diagram illustrating a cloud mail service according to the related art. Referring to FIG. 1, a system 100 for a cloud mail service may include a server, such as an Internet message access protocol (IMAP) server 110 or a post office protocol 3 (POP3) server 130, configured to receive an e-mail to be transferred to a user, a server, such as a simple mail transfer protocol (SMTP) server 120, configured to transmit an e-mail created by the user, and a storage 140 configured to store user mail content. For example, the system 100 may transfer e-mails to terminals 160 of users over a network such as the Internet 150, and may receive e-mails created by the users, from the terminals 160 of the users, to transfer the received e-mails to receivers of the e-mails through a sending server.
The cloud mail service according to the related art may reduce costs, e.g., operating costs, since construction of a separate infrastructure or a great effort for system repair and maintenance is not required. However, the cloud mail service may have security issues.
For example, mail security may be classified into a security for a transport layer regarding a safety level at which a mail is to be transmitted and a security for a storage regarding a method of safely storing a mail. Here, the transport layer may be processed in a relatively safe manner using a verified security method such as a secure sockets layer (SSL) and a transport layer security.
In terms of the security for the storage, the cloud mail service may not achieve a fundamental security irrespective of improving the security using a variety of encoding techniques such as content encoding using an encoding algorithm, encoding at a file system level, and encoding at a block device level. The cloud mail service may not achieve the fundamental security since a provider of the cloud mail service holds a key, for example, a key 170, used to encode the storage 140. Technically, the provider of the cloud mail service may decode and refer to e-mail contents of a user using the key 170 if necessary. Also, since the security of the cloud mail service is vulnerable, the key 170 may be obtained by an unauthorized user due to various security issues, such as an attack of a hacker or negligence of a manager.